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how to recognize newly added rows directly to datagridview - c#

I have bound a datatable to a datagridview and allowed the user to delete update, and insert new records directly to this datagridview
Now I want to know how do I recognize newly inserted row/rows ?
I want to get new row/rows and delete update, or insert them
into SQL server database.
How can I do it ?
Thanks

You can look into the DataTable.GetChanges method https://msdn.microsoft.com/en-us/library/thc1eetk
or better look into the DataAdapter.Update method https://learn.microsoft.com/en-us/dotnet/api/...

You can do it in 2 different ways - depend on your use case:
1st: Server side
Use this concept if you want to track the changes with multiple session per user, submit all changes to server side and track the changes datetime and save status.
2nd: Client side
Use this concept if you want to track the changes on client side regardless of the multi-session per user, basically, add 1 extra column to track the changes history -better to keep it hidden-

linq for entities hide columns from model

I am using linq for entities to read and update data from a SQL server. This database is a Dynamic NAV database, and every time someone is changing a column in the database – my application need to be recompiled.
Is it possible to ignore or hide columns in the database from linq for entities, and still get update to work correctly? Let’s say there is 100 columns in a table, and that I am using on only 10, when I update a value – I want the remaining 90 values to stay in the row.

You can just tell the people that add new columns to either
Allow null for newer columns
Or add a default constraint so a good default value is added automatically added for newer rows
Either of these will allow linq to work correctly

The best way would be to create a custom view in your database. If you want to be able to insert / update / delete from that view, you can create the appropriate triggers on the view. Linq will treat the view just like any other table.

How to keep previous and new value of data?

I’m currently working on a project where we need to archive and trace all the modified data’s.
When a modification surrender, we have to kept theses information
Who has modified the data?
When?
And … that’s why I’m asking this question: Keep the previous
and the new value of the data.
Quickly, I have to trace every modification for every data.
Example :
I have a name field why the value “Morgan”.
When I modify this value, I have to be able to say to the user that the 6th of January, by XXX, the value changed from “Morgan” to “Robert” …
I have to find a clean and generic method to do this because a large amount of data is concerned by this behavior.
My program is in C# (.NET 4) and we are using Sql Server 2008 R2 and NHibernate for the object mapping.
Do you any ideas, experience or solution about how to do a thing like that?

I am a little confused about at what point you want to have the old vs new data available. But, this can be done within a database trigger as in the following question:
trigger-insert-old-values-values-that-was-updated

NHibernate Envers its what you want :)
You must use NHibernate 3.2+ (3.2 is the current release).
Its easy like
enversConf.Audit<Person>();
You can get info here and here

I've been in the same situation as you. I ended up doing in this way:
Save an ActivityEntry in the database containing an identity column (if you have multiple objects that change), an action-indicator (could be "User changed firstname", as a int), date field, userId and most important a parameter field.
Combining the values from the parameter field and the action-indicator I'm able to make strings like "{0} changed {1}'s firstname from {2} to {3}" where my parameter values could be "John;Joe".
I know it feels kinda wrong saving these totally loosely typed values in the database, but I believe it's the only way around, without having a copy of each table.

How do I determine if a record already exists in a DataTable?

I have a DataTable that I am binding it to a GridView on my ASP.NET page. I also allow editing and insertion.
Upon saving/insertion, I need to determine if there is a duplicate description in the Gridview.
How can I accomplish this?

Any way the data which you are binding will have the unique id.
So after binding check for that id whether it is there or not in datatable.We can't say more than this unless you explain it more.

We may need some more information on what kind of database you are using to give you the right answer, but I'll take a swing anyway.
First, you need to have a PRIMARY KEY on your database table for several reasons including a default index and insuring uniqueness. Second, you can configure the table to have a UNIQUE INDEX on the description column. This will prevent the insertion of duplicate data at the database level. But, once you do that you will likely get some kind of exception or error in your client application that you will need to catch and handle.
Also, you could create an AJAX function to filter the data as the user types in the new row and show them records that are similar. I did this on an app where the users would put in the same request but use slightly different wording.

Best Practice - Handling multiple fields, user roles, and one stored procedure

I have multiple fields both asp:DropDownList's and asp:TextBox's. I also have a number of user roles that change the Visible property of certain controls so the user cannot edit them. All of this data is saved with a stored procedure call on PostBack. The problem is when I send in the parameters and the control was not on the page obviously there wasn't a value for it, so in the stored procedure I have the parameters initialized to null. However, then the previous value that was in the database that I didn't want changed is overwritten with null.
This seems to be a pretty common problem, but I didn't have a good way of explaining it. So my question is, how should I go about keeping some fields from being on the page but also keeping the values in the database all with one stored procedure?

Apply the same logic when chosing what data to update as the logic you're actually using when chosing what data (and its associated UI) to render.

I think the problem is you want to do the update of all fields in a single SQL update, regardless of their value.
I think you should do some sanity check of your input before your update, even if that implies doing individual updates for certain parameters.

Without an example, it is a little difficult to know your exact circumstances, but here is a fictitious statement that will hopefully give you some ideas. It is using t-sql (MS SQL Server) since you did not mention a specific version of SQL:
UPDATE SomeImaginaryTable
SET FakeMoneyColumn = COALESCE(#FakeMoneyValue, FakeMoneyColumn)
WHERE FakeRowID = #FakeRowID
This basically updates a column to the parameter value, unless the parameter is null, in which case it uses the columns existing value.

Generally to overcome this in my update function
I would load the current values for the user
Replacing any loaded values with the newly changed values from the form
Update in db.
This way I have all the current plus everything that has been changed will get changed.
This logic will also work for an add form because all the fields would be null then get replaced with a new value before being sent to the db. You would of course just have to check whether to do an insert or update.